Chemistry

Molar Fraction (x)


The molar fraction is a unit of concentration widely used in physical chemistry.

The value of the molar fraction of the solute as well as the solvent can be found. It is a dimensionless unit.

or

or

So:

Where:
x = molar fraction of solution
x1= molar fraction of solute
x2 = molar fraction of solvent
no1= mole number of solute
no2 = mol number of solvent
n = mol number of solution

Note:



Example:

Adding 52.0g of sucrose, C12H22O11, to 48.0g of water to form a solution, calculate the molar fraction of sucrose in this solution:

            

To find the molar fraction of the solute (sucrose):